1. Field of the Invention
The present invention relates to a machine and method for distributing ballast on a ballast bed supporting a track.
2. Description of the Prior Art
U.S. Pat. No. 5,052,132 discloses a ballast distributing and planing machine. The machine comprises a machine frame supported by undercarriages for movement along the track and is equipped with a ballast plow and a rotary broom. An elongated conveyor band leads from the broom to a ballast storage container which has a bottom conveyor band. A ballast discharge device is arranged to receive ballast from a discharge end of the bottom conveyor band. The ballast discharge device comprises four chutes spaced from each other in a direction extending transversely to the machine frame, and ballast discharge conveyors are affixed to the lower ends of the chutes. Each driven ballast discharge conveyor is pivotal about a vertical axis so that the ballast may be discharged at different sections of the track, as desired. The amount of the discharged ballast may be regulated by changing the driving speed of the ballast discharge conveyors.
A vertically adjustable wiper unit is arranged in the discharge range of each ballast discharge conveyor. It is comprised of a multiplicity of vertically extending rubber elements which form a kind of a curtain for sweeping discharged ballast from the tops of the track ties into the adjacent cribs. This lessens the amount of work to be done by the succeeding rotary broom which finishes the ballasting operation.
U.S. Pat. No. 4,794,862 and European patent No. 0 057 128 disclose ballast tamping machines carrying a ballast storage container with chutes that may be closed so that ballast, as needed, may be distributed on the track.
According to U.S. Pat. No. 5,101,733, ballast discharge chutes may be arranged in the range of the tamping tools of a ballast tamping machine. A conveyor band system conveys ballast to the chutes so that ballast be distributed in specific areas which require it.
Finally, British patent No. 2,036,142 discloses a ballast planing machine with a ballast storage container equipped with chutes for distributing ballast, as well as a rotary broom.